In the prior art, screws and pins, for example, are used for fastening implants to a tissue. A problem with screws is, however, that the fastening is slow. A problem with pins is, in some cases, an insufficient pull-out strength.
To avoid these problems, other fastening solutions have also been developed. EP1363543 describes a fastening means, which is arranged in a tissue, after which its outer surface is melted by mechanical energy. As the fastening means is simultaneously pressed against the tissue, molten surface material of the fastening means pours into the tissue pores and provides a positive locking with the tissue. A problem with this solution is that the temperature of the tissue around the fastening means may rise so high that the tissue will be damaged. U.S. Pat. No. 6,080,161 describes a fastener, which is heated as a whole to at least the transition temperature or as high as the melting temperature of the manufacturing material of the fastener. Problems here include the above mentioned heating of tissues and a relatively weak pull-out strength.